Building Trust in the Quantum Cloud with Physical Unclonable Functions

Abstract

As cloud-based quantum computing expands, securing access to quantum hardware is increasingly critical. We present an authentication protocol that leverages intrinsic quantum device properties to construct Quantum Physical Unclonable Functions (Q-PUFs). Using frequency fingerprints from fixed-frequency transmon qubits, we prototype our approach on IBM quantum devices with both real and simulated data. We employ fuzzy extractors to generate stable cryptographic keys that tolerate measurement noise and conceal raw hardware data. To support scalability, we introduce q tuples (qubit subsets) that enable challenge response generation for strong PUF behavior. We also outline extensions to neutral atom platforms and propose future directions including logical Q-PUFs. Our work lays the groundwork for secure, hardware-rooted authentication in hybrid quantum-classical systems.